Methods and apparatuses for monitoring fetal heartbeat and uterine contraction signals

ABSTRACT

Aspects of the technology described herein related to monitoring fetal heartbeat and uterine contraction signals. An ultrasound system may be configured to sweep a volume to collect ultrasound data, detect a fetal heartbeat and/or uterine contraction signal in the ultrasound data, and automatically steer an ultrasound beam to monitor the fetal heartbeat and/or uterine contraction signal. The ultrasound system may be further configured to determine a location where the fetal heartbeat and/or uterine contraction signal is detectable or detectable at a highest quality. The ultrasound system may include a wearable ultrasound device, such as an ultrasound patch coupled to a subject. The wearable ultrasound device may have a two-dimensional array of ultrasonic transducers capable of steering ultrasound beams in three dimensions.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit under 35 U.S.C. § 119(e) ofU.S. Patent Application Ser. No. 62/907,522, filed Sep. 27, 2019 underAttorney Docket No. B1348.70156US00 and entitled “METHODS ANDAPPARATUSES FOR MONITORING FETAL HEARTBEAT AND UTERINE CONTRACTIONSIGNALS,” which is hereby incorporated by reference herein in itsentirety.

FIELD

Generally, the aspects of the technology described herein relate toultrasound systems and devices. Certain aspects relate to ultrasoundsystems and devices for monitoring fetal heartbeat and/or uterinecontraction signals.

BACKGROUND

Ultrasound devices may be used to perform diagnostic imaging and/ortreatment, using sound waves with frequencies that are higher than thoseaudible to humans. Ultrasound imaging may be used to see internal softtissue body structures. When pulses of ultrasound are transmitted intotissue, sound waves of different amplitudes may be reflected backtowards the probe at different tissue interfaces. These reflected soundwaves may then be recorded and displayed as an image to the operator.The strength (amplitude) of the sound signal and the time it takes forthe wave to travel through the body may provide information used toproduce the ultrasound image. Many different types of images can beformed using ultrasound devices. For example, images can be generatedthat show two-dimensional cross-sections of tissue, blood flow, motionof tissue over time, the location of blood, the presence of specificmolecules, the stiffness of tissue, or the anatomy of athree-dimensional region.

SUMMARY

According to one aspect of the application, an apparatus includes anultrasound system configured to sweep a volume to collect ultrasounddata, detect a fetal heartbeat and/or uterine contraction signal in theultrasound data; and automatically steer an ultrasound beam to monitorthe fetal heartbeat and/or uterine contraction signal.

In some embodiments, the ultrasound data includes multiple sets ofultrasound data collected at different locations within the volume. Insome embodiments, the ultrasound system is further configured todetermine a location where the fetal heartbeat and/or uterinecontraction signal is detectable or detectable at a highest quality. Insome embodiments, the ultrasound system is further configured to sweep amodified volume to collect ultrasound data. In some embodiments, theultrasound system is further configured to determine a location wherethe fetal heartbeat and/or uterine contraction signal is detectable ordetectable at the highest quality; and the ultrasound system isconfigured, when sweeping the modified volume to collect ultrasounddata, to sweep a volume modified based on the location where the fetalheartbeat and/or uterine contraction signal was previously monitored. Insome embodiments, the modified volume is collected with a sweep that iscentered around the location where the fetal heartbeat and/or uterinecontraction signal was previously monitored.

In some embodiments, the ultrasound system includes a wearableultrasound device. In some embodiments, the wearable ultrasound deviceincludes an ultrasound patch coupled to a subject. In some embodiments,the wearable ultrasound device has a two-dimensional array of ultrasonictransducers. In some embodiments, the ultrasound system includes aprocessing device in communication with an ultrasound device. In someembodiments, the processing device includes a mobile phone, tablet,laptop, or a processing device of a standard cardiotocography (CTG)system. In some embodiments, the processing device includes theprocessing device of the standard cardiotocography system, theultrasound device includes an output port configured to couple to oneend of a cable, and another end of the cable is configured to be coupledto the processing device of the standard CTG system.

According to another aspect of the application, an apparatus includes anultrasound system configured to configure an ultrasound device tocollect multiple sets of ultrasound data from multiple regions within asubject, detect fetal heartbeat and/or uterine contraction signals fromthe collected sets of ultrasound data, and monitor the fetal heartbeatand/or uterine contraction signals by automatically configuring theultrasound device to collect further ultrasound data from a regionwithin the subject corresponding to one of the multiple sets ofultrasound data based on a quality of its fetal heartbeat and/or uterinecontraction signal.

In some embodiments, the ultrasound system is configured, whenconfiguring the ultrasound device to collect the multiple sets ofultrasound data from the multiple regions within the subject, to collecteach of the multiple sets of ultrasound data from a particular regionwithin the subject. In some embodiments, each of the multiple sets ofultrasound data includes a time series of an A-line. In someembodiments, the time series is over a sufficiently long period tocapture heartbeat motion. In some embodiments, each of the multiple setsof data includes a time series of ultrasound images collected from atwo-dimensional slice within the subject.

In some embodiments, the ultrasound system is configured, when detectingthe fetal heartbeat signals from the collected sets of ultrasound data,to use an M-mode ultrasound technique. In some embodiments, theultrasound system is configured, when detecting the fetal heartbeatsignals from the collected sets of ultrasound data, to use a statisticalmodel that is trained to detect fetal heartbeat signals in ultrasounddata. In some embodiments, the ultrasound system is configured, whendetecting the uterine contraction signals from the collected sets ofultrasound data, to use a speckle tracking technique to analyze theultrasound data for tissue contraction. In some embodiments, theultrasound system is configured, when detecting the uterine contractionsignals from the collected sets of ultrasound data, to use a statisticalmodel that is trained to measure a thickness of muscle around a uterusin ultrasound images.

In some embodiments, the ultrasound system is configured, whenautomatically configuring the ultrasound device to collect the furtherultrasound data from the region within the subject corresponding to oneof the multiple sets of ultrasound data based on the quality of itsfetal heartbeat and/or uterine contraction signal, to configure theultrasound device to use a two-dimensional array of ultrasonictransducers to steer an ultrasound beam in three dimensions to theregion in order to collect the further ultrasound data. In someembodiments, the ultrasound system is configured, when automaticallyconfiguring the ultrasound device to collect the further ultrasound datafrom the region within the subject corresponding to one of the multiplesets of ultrasound data based on the quality of its fetal heartbeatand/or uterine contraction signal, to configure the ultrasound device tocollect the further ultrasound data without collecting ultrasound datafrom other of the multiple regions within the subject. In someembodiments, the ultrasound system is configured to monitor the fetalheartbeat and/or uterine contraction signals for a period of time. Insome embodiments, the ultrasound system is configured, whenautomatically configuring the ultrasound device to collect the furtherultrasound data from the region within the subject corresponding to oneof the multiple sets of ultrasound data based on the quality of itsfetal heartbeat and/or uterine contraction signal, to configure theultrasound device to collect the further ultrasound data from a regionwithin the subject corresponding to a set of ultrasound data that has ahighest quality fetal heartbeat signal. In some embodiments, theultrasound system is configured, when automatically configuring theultrasound device to collect the further ultrasound data from the regionwithin the subject corresponding to one of the multiple sets ofultrasound data based on the quality of its fetal heartbeat and/oruterine contraction signal, to configure the ultrasound device tocollect the further ultrasound data from a region within the subjectcorresponding to a set of ultrasound data that has a highest qualityuterine contraction signal. In some embodiments, the ultrasound systemis configured, when automatically configuring the ultrasound device tocollect the further ultrasound data from the region within the subjectcorresponding to one of the multiple sets of ultrasound data based onthe quality of its fetal heartbeat and/or uterine contraction signal, toconfigure the ultrasound device to collect the further ultrasound datafrom a region within the subject corresponding to a set of ultrasounddata that has a highest combined quality of fetal heartbeat and uterinecontraction signals. In some embodiments, the combined quality of thefetal heartbeat and uterine contraction signals is a mean of a qualityof the fetal heartbeat signal and a quality of the uterine contractionsignal. In some embodiments, the quality of the fetal heartbeat signalis based on a signal-to-noise ratio (SNR) of the fetal heartbeat signal.In some embodiments, the quality of the fetal heartbeat signal is basedon a level of confidence of a statistical model that the statisticalmodel has accurately determined the fetal heartbeat signal from thefurther ultrasound data. In some embodiments, the quality of the uterinecontraction signal is based on a signal-to-noise ratio (SNR) of theuterine contraction signal. In some embodiments, the quality of theuterine contraction signal is based on a level of confidence of astatistical model that the statistical model has accurately measured athickness of a muscle around a uterus.

In some embodiments, the ultrasound system is further configured tocontinuously or periodically monitor a quality of the fetal heartbeatand/or uterine contraction signals, and to configure the ultrasounddevice to collect multiple sets of ultrasound data from a subset of themultiple regions within the subject based on the quality of the fetalheartbeat and/or uterine contraction signals not exceeding a thresholdquality. In some embodiments, the ultrasound system is furtherconfigured to configure the ultrasound device to collect multiple setsof ultrasound data from a subset of the multiple regions within thesubject. In some embodiments, the ultrasound system is configured toselect the subset of the regions based on the region from which thefurther ultrasound data was collected. In some embodiments, the subsetof the regions is a first particular percentage of regions approximatelycentered around the region within the subject from which the furtherultrasound data was collected. In some embodiments, the subset of theregions is along a spiral curve around the region within the subjectfrom which the further ultrasound data was collected.

In some embodiments, the ultrasound system is configured to monitor thefetal heartbeat and uterine contraction signals from different regionswithin the subject. In some embodiments, the ultrasound system isconfigured to steer an ultrasound beam to one region to monitor thefetal heartbeat signal and to steer the ultrasound beam to anotherregion to monitor the uterine contraction signal. In some embodiments,the ultrasound system is configured to monitor the fetal heartbeatsignal at a higher sampling rate than a sampling rate at which theuterine contraction signal is monitored.

In some embodiments, the ultrasound system is further configured tooutput the fetal heartbeat and/or uterine contraction signals fordisplay. In some embodiments, the ultrasound system is configured totransmit the fetal heartbeat and/or uterine contractions over acommunication link to a processing device configured to display thefetal heartbeat signal and/or uterine contraction signals as one or moregraphs on its display screen. In some embodiments, the processing deviceincludes a mobile phone, tablet, laptop, or a processing device of astandard cardiotocography system. In some embodiments, the processingdevice includes the processing device of the standard cardiotocographysystem, the ultrasound device includes an output port configured tocouple to one end of a cable, and another end of the cable is configuredto be coupled to the processing device of the standard CTG system.

In some embodiments, the ultrasound system includes a wearableultrasound device. In some embodiments, the wearable ultrasound deviceincludes an ultrasound patch coupled to a subject. In some embodiments,the wearable ultrasound device has a two-dimensional array of ultrasonictransducers. In some embodiments, the ultrasound system includes aprocessing device in communication with an ultrasound device. In someembodiments, the processing device includes a mobile phone, tablet,laptop, or a processing device of a standard cardiotocography system. Insome embodiments, the processing device includes the processing deviceof the standard cardiotocography system, the ultrasound device includesan output port configured to couple to one end of a cable, and anotherend of the cable is configured to be coupled to the processing device ofthe standard CTG system.

Some aspects include a method to perform the actions that the ultrasoundsystem is configured to perform.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects and embodiments will be described with reference to thefollowing exemplary and non-limiting figures. It should be appreciatedthat the figures are not necessarily drawn to scale. Items appearing inmultiple figures are indicated by the same or a similar reference numberin all the figures in which they appear.

FIG. 1 is a flow diagram illustrating an example process for monitoringa fetal heartbeat or uterine contraction signal, in accordance withcertain embodiments described herein;

FIG. 2 is another flow diagram illustrating an example process formonitoring a fetal heartbeat or uterine contraction signal, inaccordance with certain embodiments described herein;

FIG. 3 is another flow diagram illustrating an example process formonitoring a fetal heartbeat or uterine contraction signal, inaccordance with certain embodiments described herein;

FIG. 4 is another flow diagram illustrating an example process formonitoring a fetal heartbeat or uterine contraction signal, inaccordance with certain embodiments described herein;

FIG. 5 is another flow diagram illustrating an example process formonitoring a fetal heartbeat or uterine contraction signal, inaccordance with certain embodiments described herein;

FIG. 6 is another flow diagram illustrating an example process formonitoring a fetal heartbeat or uterine contraction signal, inaccordance with certain embodiments described herein;

FIG. 7 is another flow diagram illustrating an example process formonitoring a fetal heartbeat or uterine contraction signal, inaccordance with certain embodiments described herein;

FIG. 8 is a perspective view an example ultrasound patch, in accordancewith certain embodiments described herein;

FIG. 9 is an exploded view of the ultrasound patch of FIG. 8, inaccordance with certain embodiments described herein;

FIG. 10 is another exploded view of the ultrasound patch of FIG. 8, inaccordance with certain embodiments described herein;

FIG. 11 is an illustration of the ultrasound patch of FIG. 8 coupled toa patient, in accordance with certain embodiments described herein;

FIG. 12 is a perspective view of another example ultrasound patch, inaccordance with certain embodiments described herein;

FIG. 13 is an illustration of an example alternative fastening mechanismfor an ultrasound patch, in accordance with certain embodimentsdescribed herein;

FIG. 14 is an illustration of the ultrasound patch of FIG. 13 fastenedto a patient, in accordance with certain embodiments described herein;and

FIG. 15 is a schematic block diagram of an example ultrasound system, inaccordance with certain embodiments described herein.

DETAILED DESCRIPTION

During labor, it may be desirable to monitor fetal heartbeat and/oruterine contraction signals. While transducers in a cardiotocographysystem can be coupled adjacent to a subject's uterus for monitoring suchsignals, due to movement of the subject and/or the fetus, a transducermay be able to detect the fetal heartbeat and/or uterine contractionsignals at one location on the subject but not be able to detect thesignals a period of time later. Thus, frequent manual readjustment ofthe positions of the transducers may be needed. The same need toreadjust the positions of transducers may also occur during extended athome monitoring (e.g., in the case of a high-risk pregnancy) of fetalheartbeat and/or uterine contraction signals before labor.

Recently, ultrasound-on-chips incorporating ultrasound circuitry and atwo-dimensional array of a large number of ultrasonic transducers on anintegrated circuit have been developed. The large ultrasound transducerarray may allow such an ultrasound-on-chip to have advanced imagingfunctionality. For example, the two-dimensional ultrasound transducerarray may enable an ultrasound beam to be steered in three dimensionsand collect three-dimensional ultrasound data from a volume within thesubject. The ultrasound-on-chip may be sufficiently small in size toform the core of a wearable ultrasound device. The wearable ultrasounddevice may be in the form-factor of an ultrasound patch or some otherform-factor that can couple to a subject. In some embodiments, thewearable ultrasound device may be self-contained in that it may includeultrasound transducers, transmit circuitry, and receive circuitry, aportion or all of which may be included in an ultrasound-on-chip. Thetransmit circuitry may include, for example, high-voltage pulsersconfigured to drive the ultrasonic transducers to emit ultrasound. Thereceive circuitry may include, for example, analog and digital circuitryconfigured to (in no particular order) receive analog ultrasoundsignals; digitize the analog ultrasound signals; filter compress,beamform, and/or form ultrasound images from ultrasound signals; andcontrol and coordinate different parts of the circuitry to work insynchronization with one another. In some embodiments, the wearableultrasound device may be capable of generating ultrasound images fromultrasound signals it itself collects with ultrasound transducerslocated on the wearable ultrasound device. In some embodiments, thewearable ultrasound device may not be coupled to another processingdevice.

In some embodiments, such a wearable ultrasound device may be less than1 kg in weight. In some embodiments, such a wearable ultrasound devicemay be less than 0.5 kg in weight. In some embodiments, such a wearableultrasound device may be less than 0.25 kg in weight. In someembodiments, such a wearable ultrasound device may be less than 5 cm inthickness. In some embodiments, such a wearable ultrasound device may beless than 2.5 cm in thickness. In some embodiments, such a wearableultrasound device may be less than 1.25 cm in thickness. In someembodiments, such a wearable ultrasound device may be less than 1 cm inthickness. In some embodiments, such a wearable ultrasound device may beless than 180 cm³ in volume. In some embodiments, such a wearableultrasound device may be less than 90 cm³ in volume. In someembodiments, such a wearable ultrasound device may be less than 45 cm³in volume. In some embodiments, such a wearable ultrasound device may beless than 25 cm³ in volume. In some embodiments, such a wearableultrasound device may be less than 15 cm³ in volume. In someembodiments, such a wearable ultrasound device may be less than 6 cm³ involume.

For further description of ultrasound-on-chips, see U.S. patentapplication Ser. No. 15/626,711 titled “UNIVERSAL ULTRASOUND DEVICE ANDRELATED APPARATUS AND METHODS,” filed on Jun. 19, 2017 and published asU.S. Pat. App. Publication No. 2017-0360399 A1 (and assigned to theassignee of the instant application) and/or U.S. patent application Ser.No. 16/192,603 titled “ULTRASOUND APPARATUSES AND METHODS FORFABRICATING ULTRASOUND DEVICES,” filed on Nov. 15, 2018 and published asU.S. Pat. App. Publication No. 2019-0142387 A1, both of which areincorporated by reference herein in their entireties.

The inventors have recognized that such a wearable ultrasound device(e.g., a patch) including an ultrasound-on-chip may be configured as afetal heart and/or uterine contraction monitor. In particular, theinventors have recognized that the capability of the wearable ultrasounddevice, with the two-dimensional ultrasound transducer array of itsultrasound-on-chip, to steer ultrasound beams in three dimensions mayenable the wearable ultrasound device to automatically track fetalheartbeat and/or uterine contraction signals as the subject and/or fetusmove. In some embodiments, the wearable ultrasound device may beconfigured to implement searching algorithms that may scan the imagespace to find the fetal heartbeat and/or uterine contraction signal, andthen implement tracking algorithms to keep the signal in focus while thesignal is monitored. Scanning the image space may include collectingultrasound data from a volume within the subject to find a locationwhere the strongest fetal heartbeat and/or uterine contraction signalmay be detected. The wearable ultrasound device may then automaticallysteer an ultrasound beam to that location. Keeping the signal in focuswhile the signal is monitored may include periodically collectingultrasound data from a smaller volume near the previously monitoredlocation to determine if, due to movement of the subject and/or fetus,the ultrasound beam should be re-steered to a new location where thestrongest fetal heartbeat and/or uterine contraction signal may bedetected.

It should be appreciated that the embodiments described herein may beimplemented in any of numerous ways. Examples of specificimplementations are provided below for illustrative purposes only. Itshould be appreciated that these embodiments and thefeatures/capabilities provided may be used individually, all together,or in any combination of two or more, as aspects of the technologydescribed herein are not limited in this respect.

FIGS. 1-7 are flow diagrams illustrating example processes 100-700 formonitoring a fetal heartbeat or uterine contraction signal, inaccordance with certain embodiments described herein. The process 100 isa general process and further detail of the process 100 may be foundwith reference to the processes 200-700. The processes 100-700 areperformed by an ultrasound system. The ultrasound system includes anultrasound device configured to collect ultrasound data from a subject.In some embodiments, the ultrasound device may be a wearable ultrasounddevice such as an ultrasound patch coupled to a subject, and inparticular, to a region adjacent to the subject's uterus. In someembodiments, the ultrasound device may include an ultrasound-on-chip. Insome embodiments, the ultrasound system may also include a processingdevice in communication with the ultrasound device. The processingdevice may be, for example, a mobile phone, tablet, laptop, theprocessing device of a standard cardiotocography (CTG) system (e.g., theportions of a CTG system excluding the transducers), or another type ofelectronic device in communication with the ultrasound device. Inembodiments that include an ultrasound device and a processing device,the ultrasound device and the processing device may communicate over awired communication link (e.g., over Ethernet, a Universal Serial Bus(USB) cable or a Lightning cable) or over a wireless communication link(e.g., over a BLUETOOTH, WiFi, ZIGBEE, or cellular (e.g., 3G, LTE, orCAT-M1) wireless communication link). In embodiments in which theprocessing device is a processing device of a standard CTG system, theultrasound device may include an output port configured to couple to oneend of a cable, the other end of which is configured to be coupled tothe processing device of the CTG system. For example, in the case of USBcommunication, the ultrasound device may include a USB port andcircuitry capable of communication according to the USB protocol. Insome embodiments, the ultrasound system may not include a processingdevice. In some embodiments, the processing device may perform all ofthe processes 100-700. In some embodiments, the ultrasound device (e.g.,an ultrasound patch) may perform the processes 100-700. In someembodiments, the ultrasound device may perform portions of the processes100-700 and the processing device may perform other portions of theprocesses 100-700. Any of the processes 100-700 may be used, forexample, for monitoring fetal heartbeat and/or uterine contractionsignals during labor or for extended at home monitoring (e.g., in thecase of a high-risk pregnancy).

In act 102 of the process 100, the ultrasound system sweeps a volume tocollect ultrasound data. The ultrasound data may include multiple setsof ultrasound data collected at different locations within the volume.In some embodiments, the processing device may configure the ultrasounddevice to sweep the volume to collect the ultrasound data. In someembodiments, the ultrasound device may configure itself to sweep thevolume to collect the ultrasound data. The process 100 proceeds from act102 to act 104.

In act 104, the ultrasound system detects a fetal heartbeat and/oruterine contraction signal in the ultrasound data collected in act 102.The ultrasound system may determine the location where the fetalheartbeat and/or uterine contraction signal is detectable and/ordetectable at the highest quality. In some embodiments, the processingdevice may detect the fetal heartbeat and/or uterine contraction signalin the ultrasound data. In some embodiments, the ultrasound device maydetect the fetal heartbeat and/or uterine contraction signal in theultrasound data. The process 100 proceeds from act 104 to act 106.

In act 106, the ultrasound system automatically steers an ultrasoundbeam to monitor the fetal heartbeat and/or uterine contraction signalthat was detected in act 104. In particular, the ultrasound system maysteer the ultrasound beam to the location that was determined in act104. In some embodiments, the processing device may configure theultrasound device to steer the ultrasound beam to monitor the fetalheartbeat and/or uterine contraction signal. In some embodiments, theultrasound device may configure itself to steer the ultrasound beam tomonitor the fetal heartbeat and/or uterine contraction signal.

As illustrated in FIG. 1, the ultrasound system at act 106 may,optionally, also perform acts 106 a and 106 b. In act 106 a, theultrasound system determines whether the monitored fetal heartbeatsignal indicates a medically noteworthy fetal heartbeat signal. In someembodiments, to make this determination, the ultrasound device maydetermine the fetal heart rate from the fetal heartbeat signal, and thendetermine whether the fetal heart rate is medically noteworthy. Forexample, a medically noteworthy fetal heart rate may be a heart ratethat exceeds a certain threshold heart rate or is below a certainthreshold heart rate. If the ultrasound system determines that themonitored fetal heartbeat signal indicates a medically noteworthy fetalheartbeat signal, then process 100 proceeds to act 108. If theultrasound system determines that the monitored fetal heartbeat signalindicates a medically noteworthy fetal heartbeat signal, then process100 proceeds to act 106 b, in which the ultrasound system generates anotification regarding the medically noteworthy fetal heartbeat signal.In some embodiments, the ultrasound device may perform the determinationin act 106 a and generate the notification in act 106 b and, as part ofact 106 b, transmit the notification to the processing device over awired communication link (e.g., over Ethernet, a Universal Serial Bus(USB) cable or a Lightning cable) or over a wireless communication link(e.g., over a BLUETOOTH, WiFi, ZIGBEE, or cellular (e.g., 3G, LTE, orCAT-M1) wireless communication link. In some embodiments, the processingdevice may perform the determination in act 106 a and generate thenotification in act 106 b. The notification may include, for example, adisplay on the processing device of the fetal heart rate, a display asto whether the heart rate is too high or too low, and/or an auditoryalarm generated by the processing device. However, other forms ofnotifications may be used as well. The process proceeds from act 106 bto act 108. If the ultrasound system does not perform acts 106 a and 106b, then the process 100 proceeds from act 106 to 108. While acts 106 aand 106 b are described and illustrated with regards to medicallynoteworthy fetal heartbeat signals, in other embodiments acts 106 a and106 b may determine medically noteworthy uterine contraction signals andgenerate notifications regarding the same.

The ultrasound system may monitor the fetal heartbeat and/or uterinecontraction signal in act 106 for a period of time. However, after theperiod of time, due to movement of the fetus and/or the subject, thefetal heartbeat and/or uterine contraction may no longer be detectable,or detectable at a sufficient level of quality, or detectable at thehighest available level of quality, at the location to which theultrasound system steered the ultrasound beam in act 106. Accordingly,in act 108, the ultrasound system sweeps a modified volume to collectultrasound data. The sweep may be modified from the sweep in act 102based on the location the fetal heartbeat and/or uterine contractionsignal was previously monitored in act 106. For example, the modifiedvolume may be a smaller volume that is centered around the previousmonitoring location. Thus, the sweep in act 108 may be considered anarrow sweep, while the sweep in act 102 may be considered a wide sweep.The process proceeds from act 108 back to act 104. Thus, afterperforming the modified sweep in act 108, in act 104, the ultrasoundsystem detects the fetal heartbeat and/or uterine contraction signalfrom the sweep again, and in act 106, the ultrasound system steers theultrasound beam (potentially to a different location than the previouslocation) for further monitoring.

Referring now to FIG. 2, in the process 200, act 202 may correspond toact 102, act 204 may correspond to act 104, act 206 may correspond toact 106, and acts 208-214 and 216 may correspond to act 108.

In act 202 of the process 200, the ultrasound system configures theultrasound device to collect multiple sets of ultrasound data frommultiple regions within a subject. As referred to herein, a region maybe any set of locations. Each set of ultrasound data may be collectedfrom a particular region within the subject. The ultrasound system maybe considered to perform an ultrasound sweep in act 202. In someembodiments, the ultrasound device may configure itself to collect themultiple sets of ultrasound data. In some embodiments, a processingdevice in communication with the ultrasound device may configure theultrasound device (e.g., by transmitting commands over a communicationlink) to collect the multiple sets of ultrasound data. In someembodiments, each of the multiple sets of data may be a time series ofan A-line. The ultrasound system may configure the ultrasound device tocollect the multiple A-lines through rastering along a single dimension,multiple dimensions, or through scanning along a curve (e.g., a spiral)in space. The time series may be over a sufficiently long period tocapture heartbeat motion. In some embodiments, each of the multiple setsof data may be a time series of ultrasound images collected from atwo-dimensional slice within the subject. Ultrasound images from each ofthe two-dimensional slices may be collected at a different elevationalangle or azimuthal angle with respect to a transducer array of theultrasound device. In some embodiments, collecting ultrasound imagesfrom a two-dimensional slice may include raster collection of A-linesalong a single dimension. In some embodiments, collecting ultrasoundimages from a two-dimensional slice include multiple raster collectionsof A-lines at multiple different angles with respect to a transducerarray of the ultrasound device, using techniques such as spatialcompounding. In some embodiments, collecting ultrasound images from atwo-dimensional slice may include raster collection of ultrasound datausing illumination techniques such as plane waves or diverging beamswhich may not necessarily be focused A-lines. In some embodiments,collecting ultrasound images from a two-dimensional slice may includeusing techniques such as synthetic aperture techniques, wherereconstruction along a particular direction may not be complete untilseveral directions have been combined with it. In some embodiments,multiple sets of ultrasound images from multiple two-dimensional slicesmay together constitute a three-dimensional volume. The process 200proceeds from act 202 to act 204.

In act 204, the ultrasound system detects fetal heartbeat signals fromthe sets of ultrasound data collected in act 202. In some embodiments,detecting fetal heartbeat signals may include using an M-mode ultrasoundtechnique. In embodiments in which the ultrasound data includes A-lines,the M-mode ultrasound technique may be applied directly to the A-lines.In embodiments in which the ultrasound data includes ultrasound imagesfrom two-dimensional slices, the M-mode technique may be applied toparticular A-lines within the two-dimensional ultrasound images. In someembodiments, detecting fetal heartbeat signals may include using astatistical model that is trained to detect fetal heartbeat signals inultrasound data. For example, the statistical model may be trained toclassify ultrasound images as belonging to a particular phase of theheartbeat cycle (e.g., systole or diastole), and the heartbeat signal(e.g., the heartrate) may be detected by determining the time betweensuccessive beginnings of the phase of the heartbeat cycle. Any of thestatistical models discussed herein may be, for example, a convolutionalneural network, a fully connected neural network, a recurrent neuralnetwork (e.g., a long short-term memory (LSTM) recurrent neuralnetwork), a random forest, a support vector machine, a linearclassifier, and/or any other statistical model. Any of the statisticalmodels described in this application may be stored and run on theultrasound device. For example, the ultrasound device may include one ormore chips designed for operating statistical models. The chips may beartificial intelligence (AI) accelerator chips, such as tensorprocessing units (TPUs)). Alternatively, any of the statistical modelsdescribed in this application may be stored and run on a processingdevice in communication with the ultrasound device or on an electronicdevice accessed by the ultrasound device or the processing device.Further description of detecting fetal heartbeat signals may be found inPeters et. al., Monitoring the fetal heart non-invasively: A review ofmethods, Journal of perinatal medicine, 2001, the content of which isincorporated by reference herein in its entirety. In some embodiments,the ultrasound device may perform the detection in act 204. In someembodiments, a processing device in communication with the ultrasounddevice may perform the detection in act 204. The process 200 proceedsfrom act 204 to act 206.

In act 206, the ultrasound system automatically configures theultrasound device to collect further ultrasound data from a regionwithin the subject. The region corresponds to a set of ultrasound databased on a quality of its fetal heartbeat signal. The region may be theregion from which the set of ultrasound data was collected in act 202.The ultrasound system may configure the ultrasound device to use itstwo-dimensional array of ultrasonic transducers to steer an ultrasoundbeam in three dimensions to the region in order to collect the furtherultrasound data. The ultrasound system may configure the ultrasounddevice to collect this ultrasound data without collecting ultrasounddata from the other regions from which ultrasound data was collected inact 202. Based on the ultrasound data collected in act 206, theultrasound system may detect a fetal heartbeat signal (e.g., using thetechniques described with reference to act 204). Thus, act 206 mayconstitute monitoring of the fetal heartbeat signal, and may beperformed for a period of time. In some embodiments, the quality of afetal heartbeat signal may be based on the signal-to-noise ratio (SNR)of the fetal heartbeat signal (e.g., the SNR of the M-mode data fromwhich the fetal heartbeat signal is determined). In some embodiments,the quality of a fetal heartbeat signal may be based on the level ofconfidence of a statistical model that the statistical model hasaccurately determined the fetal heartbeat signal from ultrasound data.For example, the level of confidence may be related to a level ofconfidence the statistical model has that it has accurately classifiedultrasound images as belonging to a particular phase of the heartbeatcycle (e.g., systole or diastole). In some embodiments, the ultrasoundsystem may configure the ultrasound device to collect further ultrasounddata from a region within the subject corresponding to a set ofultrasound data that has the highest quality. In some embodiments, theultrasound device may determine the quality in act 206. In someembodiments, a processing device in communication with the ultrasounddevice may determine the quality in act 206. In some embodiments, theultrasound device may configure itself to collect the further ultrasounddata. In some embodiments, a processing device in communication with theultrasound device may configure the ultrasound device to collect thefurther ultrasound data (e.g., by transmitting commands over acommunication link). The process 200 proceeds from act 206 to act 208.

The ultrasound system may collect further ultrasound data, and therebymonitor the fetal heartbeat signal, in act 206 for a period of time.However, due to movement of the fetus and/or the subject, the fetalheartbeat may no longer be detectable, or no longer be detectable at asufficient level of quality, or no longer be detectable at the highestavailable level of quality, at the region from which the ultrasoundsystem is collecting data in act 206. Accordingly, the ultrasound systemperforms another ultrasound sweep in act 208. Act 208 may occur a setperiod of time after act 206 (i.e., after a set period of monitoring).Based on the assumption that the fetus and/or subject has not moved anextreme amount during the monitoring period, the ultrasound system maynot perform a sweep over all the regions from act 202. Instead, theultrasound system performs a modified sweep over a subset of theselocations, in which the ultrasound system may search around thepreviously monitored region. Thus, the sweep of act 202 may beconsidered a wide sweep while the sweep of act 208 may be considered anarrow sweep.

In some embodiments, the narrow sweep may be any sweep that is smallerthan the wide sweep. For example, consider that the wide sweep andnarrow sweep are sweeps of A-lines. In some embodiments, the wide sweepmay be over a span in the azimuthal direction, elevational direction, orboth azimuthal and elevation directions (i.e., defining a solid angle)of 40 degrees, 50 degrees, 60 degrees, 70 degrees, 80 degrees, 90degrees, 100 degrees, 110 degrees, 120 degrees, or any other span ofdegrees in between these values. In some embodiments, the narrow sweepmay be over a span in the azimuthal direction, elevational direction, orboth azimuthal and elevation directions (i.e., defining a solid angle)of 5 degrees, 10 degrees, 15 degrees, or any other span of degrees inbetween these values. (It should be appreciated that a sweep that spansX degrees may mean that the sweep proceeds from −X/2 to X/2 degrees.) Asanother example, consider that the wide sweep and narrow sweep aresweeps of ultrasound images. In some embodiments, the wide sweep may beover a span in the elevational direction of 40 degrees, 50 degrees, 60degrees, 70 degrees, 80 degrees, 90 degrees, 100 degrees, 110 degrees,120 degrees, or any other span of degrees in between these values. Insome embodiments, the narrow sweep may be over a span in the elevationaldirection of 5 degrees, 10 degrees, 15 degrees, or any other span ofdegrees in between these values.

In act 208, the ultrasound system configures the ultrasound device tocollect multiple sets of ultrasound data from a subset of the multipleregions within the subject (from which ultrasound data was collected inact 202). In some embodiments, the ultrasound system may select thesubset of the regions based on the region from which further ultrasounddata was collected in act 206 (which may be referred to hereinafter as“the monitored region”). In some embodiments, the ultrasound system mayconfigure the ultrasound device to collect ultrasound data from X %(where X is a number between 0 and 100) of the regions from whichultrasound data was collected in act 202. In some embodiments, thesubset of the regions may be the first X % of the regions that areapproximately centered around the monitored region. For example, theultrasound system may configure the ultrasound device to collectultrasound data with raster scanning, and the approximate center of theraster scan may be the monitored region. As another example, theultrasound system may configure the ultrasound device to collectultrasound data along a spiral curve around the monitored region. Insome embodiments, the ultrasound device may configure itself to collectthe multiple sets of ultrasound data. In some embodiments, a processingdevice in communication with the ultrasound device may configure theultrasound device (e.g., by transmitting commands over a communicationlink) to collect the multiple sets of ultrasound data. The process 200proceeds from act 208 to act 210.

In act 210, the ultrasound system detects fetal heartbeat signals fromthe sets of ultrasound data collected in act 208. Further description ofdetecting fetal heartbeat signals may be found with reference to act204. The process 200 proceeds from act 210 to act 212.

In act 212, the ultrasound system determines whether a quality of afetal heartbeat signal in the collected sets of ultrasound data (fromact 208) exceeds a threshold quality. Regarding the quality of a fetalheartbeat signal, in some embodiments, the ultrasound system maydetermine whether a signal-to-noise ratio (SNR) of a fetal heartbeatsignal (e.g., the SNR of the M-mode data from which the fetal heartbeatsignal is determined) in any of the collected ultrasound data exceeds athreshold SNR. In some embodiments, the ultrasound system may determinewhether a statistical model has accurately determined the fetalheartbeat signal from any of the collected ultrasound data with a levelof confidence exceeding a threshold level of confidence. In someembodiments, the ultrasound device may perform the determination in act212. In some embodiments, a processing device in communication with theultrasound device may perform the determination in act 212. If theultrasound system determines that a quality of fetal heartbeat signal inthe collected ultrasound data exceeds a threshold quality, the process200 proceeds from act 212 to act 206. In act 206, the ultrasound systemagain performs monitoring of the fetal heartbeat, but may collectultrasound data for this monitoring from a different region than in theprevious iteration through act 206. In some embodiments, the ultrasoundsystem may configure the ultrasound device to collect further ultrasounddata from a region within the subject corresponding to a set ofultrasound data collected in act 208 that has the highest quality. Ifthe ultrasound system determines that a quality of a fetal heartbeatsignal in the collected ultrasound data does not exceed a thresholdquality, the process 200 proceeds from act 212 to act 214.

In act 214, the ultrasound system configures the ultrasound device tocollect multiple sets of ultrasound data from another subset of themultiple regions within the subject (i.e., different from the subset ofact 208). In some embodiments, the ultrasound system may configure theultrasound device to collect ultrasound data from the next Y % regions(i.e., the next Y % after the first X %, where Y is a number between 0and 100−X) from which ultrasound data was collected in act 202. In someembodiments, the subset of the regions may be the next Y % of theregions that are centered around the monitored region. In other words,the ultrasound system may search further (compared with the search fromact 208) around the monitored region. In some embodiments, theultrasound device may configure itself to collect the multiple sets ofultrasound data. In some embodiments, a processing device incommunication with the ultrasound device may configure the ultrasounddevice (e.g., by transmitting commands over a communication link) tocollect the multiple sets of ultrasound data. The process proceeds fromact 214 to act 210, in which the ultrasound system detects fetalheartbeat signals from the sets of ultrasound data collected in act 214.

In some embodiments, acts 208-214 may be absent. For example, theultrasound system may configure the ultrasound device to collectultrasound data from a particular region in act 206 and not determinewhether the ultrasound beam should be subsequently re-steered. Or, insome embodiments, the process 200 may proceed from act 206 to act 202.In other words, after a monitoring period, the ultrasound system mayperform a wide sweep rather than a narrow sweep. In some embodiments,acts 212-214 may be absent. For example, the ultrasound system mayconfigure the ultrasound device to collect ultrasound data from aparticular region scanned in act 208 regardless of whether ultrasounddata collected in act 208 exceeds a threshold quality.

Referring now to FIG. 3, in the process 300, act 302 may correspond toact 102, act 304 may correspond to act 104, acts 306-308 may correspondto act 106, and act 310 may correspond to act 108.

In act 302, the ultrasound system configures an ultrasound device tocollect multiple sets of ultrasound data from multiple regions within asubject. Further description of act 302 may be found with reference toact 202. The process 300 proceeds from act 302 to act 304.

In act 304, the ultrasound system detects fetal heartbeat signals fromthe collected sets of ultrasound data. Further description of act 304may be found with reference to act 204. The process 300 proceeds fromact 304 to act 306.

In act 306, the ultrasound system automatically configures theultrasound device to collect further ultrasound data from a regionwithin the subject corresponding to a set of ultrasound data based on aquality of its fetal heartbeat signal. Further description of act 306may be found with reference to act 306. The process 300 proceeds fromact 306 to act 308.

In act 308, the ultrasound system determines whether a quality of afetal heartbeat signal in the collected sets of ultrasound data (fromact 306) exceeds a threshold quality. Further description of act 308 maybe found with reference to act 212. In some embodiments, the ultrasoundsystem may perform act 308 continuously on ultrasound data collected inact 306. In some embodiments, the ultrasound system may perform act 308periodically on ultrasound data collected in act 306. If the ultrasoundsystem determines that a quality of a fetal heartbeat signal in thecollected ultrasound data exceeds a threshold quality, the process 300repeats act 308, in which the ultrasound system continues to collect thefetal heartbeat signal and determine if the quality of the collectedfetal heartbeat signal exceeds a threshold quality or not. If theultrasound system determines that a quality of fetal heartbeat signal inthe collected ultrasound data does not exceed a threshold quality, theprocess 300 proceeds from act 308 to act 310.

In act 310, the ultrasound system configures the ultrasound device tocollect multiple sets of ultrasound data from a subset of the multipleregions within the subject. Further description of act 310 may be foundwith reference to act 208. Act 310 includes performing a modified sweepcompared with the sweep of act 302. In some embodiments, the ultrasoundsystem may configure the ultrasound device to collect ultrasound datafrom X % (where X is a number between 0 and 100) of the regions fromwhich ultrasound data was collected in act 302. In some embodiments, thesubset of the regions may be the first X % of the regions that arecentered around the monitored region. If, on the next iteration throughact 308, the ultrasound system determines that a quality of fetalheartbeat signal in the collected ultrasound data does not exceed athreshold quality, in act 310, the ultrasound system may configure theultrasound device to collect ultrasound data from the next Y % (where Yis a number between 0 and 100−X) of the regions from which ultrasounddata was collected in the previous iteration through act 310.

In some embodiments, acts 308-310 may be absent. For example, theultrasound system may configure the ultrasound device to collectultrasound data from a particular region in act 306 and not determinewhether the ultrasound beam should be subsequently re-steered. Or, insome embodiments, the process 300 may proceed from act 306 to act 302.In other words, after a monitoring period, the ultrasound system mayperform a wide sweep rather than a narrow sweep.

It should be appreciated that in the process 300, during monitoring ofthe fetal heartbeat signal, the ultrasound system may continuously orperiodically monitor the quality of the signal. If the quality of signalfalls below a threshold, the ultrasound system may perform a modifiedsweep to search for a new region from which to measure the fetalheartbeats. Otherwise, the ultrasound system may continue to monitor thesignal from the same location. In contrast, in the process 200, theultrasound system may perform the modified sweep after a monitoringperiod whether or not the quality of the signal has fallen below athreshold.

Referring now to FIG. 4, the process 400 is the same as the process 200,except that in the process 400, the ultrasound system searches for andmonitors a uterine contraction signal rather than a fetal heartbeatsignal. In some embodiments, detecting uterine contraction signals(e.g., in acts 404, 406, 410) may include using a speckle trackingtechnique to analyze ultrasound data for tissue contraction. Inembodiments in which the ultrasound data includes A-lines, theultrasound system may use speckle tracking techniques applied directlyto the A-lines. In embodiments in which the ultrasound data includesultrasound images from two-dimensional slices, the speckle trackingtechniques may be applied to the two-dimensional ultrasound images. Insome embodiments, detecting uterine contraction signals may includeusing a statistical model that is trained to measure the thickness ofthe muscle around the uterus in ultrasound images. The ultrasound systemmay detect contractions by detecting changes in thickness (as determinedby the statistical model) that exceed a threshold. In some embodiments,the quality of a uterine contraction signal (as determined in acts 406and 412) may be based on the signal-to-noise ratio (SNR) of the uterinecontraction signal (e.g., the SNR of the speckle tracking data fromwhich the uterine contraction signal is determined). In someembodiments, the quality of a uterine contraction signal may be based onthe level of confidence of a statistical model that the statisticalmodel has accurately measured the thickness of the muscle around theuterus. In some embodiments, detecting the uterine contraction signalsand/or determining the quality of the uterine contraction signal may beperformed by the ultrasound device. In some embodiments, detecting theuterine contraction signals and/or determining the quality of theuterine contraction signal may be performed by a processing device incommunication with the ultrasound device.

In some embodiments, acts 408-414 may be absent. For example, theultrasound system may configure the ultrasound device to collectultrasound data from a particular region in act 406 and not determinewhether the ultrasound beam should be subsequently re-steered. Or, insome embodiments, the process 400 may proceed from act 406 to act 402.In other words, after a monitoring period, the ultrasound system mayperform a wide sweep rather than a narrow sweep. In some embodiments,acts 412-414 may be absent. For example, the ultrasound system mayconfigure the ultrasound device to collect ultrasound data from aparticular region scanned in act 408 regardless of whether ultrasounddata collected in act 408 exceeds a threshold quality.

Referring now to FIG. 5, the process 500 is the same as the process 300,except that in the process 500, the ultrasound system searches for andmonitors and uterine contraction signal rather than a fetal heartbeatsignal. Further description of detecting uterine contraction signals(e.g., in acts 504 and 506) and determining the quality of a uterinecontraction signal (as determined in acts 506 and 508) may be found withreference to the process 400. In some embodiments, detecting the uterinecontraction signals and/or determining the quality of the uterinecontraction signal may be performed by the ultrasound device. In someembodiments, detecting the uterine contraction signals and/ordetermining the quality of the uterine contraction signal may beperformed by a processing device in communication with the ultrasounddevice.

In some embodiments, acts 508-510 may be absent. For example, theultrasound system may configure the ultrasound device to collectultrasound data from a particular region in act 506 and not determinewhether the ultrasound beam should be subsequently re-steered. Or, insome embodiments, the process 500 may proceed from act 506 to act 502.In other words, after a monitoring period, the ultrasound system mayperform a wide sweep rather than a narrow sweep

In some embodiments, either the process 200 or 300 may be combined witheither the process 400 or 500. For example, the ultrasound system mayperform acts 202-204 and 402-404 (i.e., searching for fetal heartbeatand uterine contraction signals with a wide sweep) and then perform acts206 and 406 (i.e., monitoring the fetal heartbeat and uterinecontraction signals). It should be appreciated that the ultrasoundsystem may monitor the fetal heartbeat and uterine contraction signalsfrom different regions within the subject. In other words, theultrasound system may steer an ultrasound beam to one region to monitorthe fetal heartbeat signal and steer the ultrasound beam to anotherregion to monitor the uterine contraction signal. It should also beappreciated that the ultrasound system may monitor (i.e., in act 206)the fetal heartbeat signal at a higher sampling rate than the samplingrate at which the uterine contraction signal is monitored (i.e., in act406) because the heartrate may be faster than the rate of contractions.For example, the sampling rate for the fetal heartbeat signal may beapproximately 20-30 frames of ultrasound data per second and thesampling rate for the uterine contraction signal may be approximately 1frame of ultrasound data per second. The ultrasound system may thenperform acts 208-214 and 408-414 (i.e., searching for fetal heartbeatand uterine contraction signals with a narrow sweep) and then performacts 206 and 406 (i.e., monitoring the fetal heartbeat and uterinecontraction signals) again.

As another example, the ultrasound system may perform acts 302-304 and502-504 (i.e., searching for fetal heartbeat and uterine contractionsignals with a wide sweep) and then perform acts 306 and 506 (i.e.,monitoring the fetal heartbeat and uterine contraction signals). Itshould be appreciated that the ultrasound system may monitor the fetalheartbeat and uterine contraction signals from different regions withinthe subject. In other words, the ultrasound system may steer anultrasound beam to one region to monitor the fetal heartbeat and steerthe ultrasound beam to another region to monitor the uterine contractionsignal. It should also be appreciated that the ultrasound system maymonitor (i.e., in act 306) the fetal heartbeat signal at a highersampling rate than the sampling rate at which the uterine contractionsignal is monitored (i.e., in act 506) because the heartrate may befaster than the rate of contractions. For example, the sampling rate forthe fetal heartbeat signal may be approximately 20-30 frames ofultrasound data per second and the sampling rate for the uterinecontraction signal may be approximately 1 frame of ultrasound data persecond. The ultrasound system may then perform acts 308 and 508 (i.e.,determine whether to search for the fetal heartbeat or uterinecontraction signal with a narrow sweep) and perform acts 310 and/or 410(i.e., perform the narrow sweep) depending on the result of acts 308 and508. For example, the ultrasound system may re-steer the ultrasound beamjust for monitoring the fetal heartbeat signal, but not re-steer theultrasound beam for monitoring the uterine contraction signal, or viceversa.

Referring now to FIG. 6, the process 600 is the same as the processes200 and 400, with the following differences. In acts 604 and 610, theultrasound system detects fetal heartbeat and/or uterine contractionsignals from the collected sets of ultrasound data. Further descriptionof detecting fetal heartbeat signals may be found with reference to theprocess 200. Further description of detecting fetal heartbeat signalsmay be found with reference to the process 400. In some embodiments, theultrasound system may detect both fetal heartbeat and uterinecontraction signals from the collected sets of ultrasound data. In someembodiments, the ultrasound system may detect either fetal heartbeat oruterine contraction signals from the collected sets of ultrasound data.

In act 606, the ultrasound system automatically configures theultrasound device to collect further ultrasound data from a regionwithin the subject corresponding to a set of ultrasound data based on aquality of its fetal heartbeat and/or uterine contraction signal.Further description of determining the quality of a fetal heartbeatsignal and configuring the ultrasound device may be found with referenceto the process 200. Further description of determining the quality of auterine contraction signal and configuring the ultrasound device may befound with reference to the process 400. In some embodiments, the regionmay be the region from which the set of ultrasound data having thehighest quality fetal heartbeat signal was collected. In someembodiments, the region may be the region from which the set ofultrasound data having the highest quality uterine contraction signalwas collected. In some embodiments, the region may be the region fromwhich the set of ultrasound data having the highest combined quality ofits fetal heartbeat and uterine contraction signals was collected. Forexample, the combined quality may be the mean (e.g., arithmetic orgeometric) of the quality of the fetal heartbeat signal and the qualityof the uterine contraction signal. It should also be appreciated thatthe ultrasound system may monitor fetal heartbeat signal at a highersampling rate than the sampling rate at which the uterine contractionsignal is monitored because the heartrate may be faster than the rate ofcontractions. For example, the sampling rate for the fetal heartbeatsignal may be approximately 20-30 frames of ultrasound data per secondand the sampling rate for the uterine contraction signal may beapproximately 1 frame of ultrasound data per second.

In act 612, the ultrasound system determines if a quality of a fetalheartbeat and/or uterine contraction signal in the collected sets ofultrasound data exceed a threshold quality. In some embodiments, theprocess 600 may proceed to act 614 if the quality of the fetal heartbeatsignal does not exceed a threshold quality, and otherwise proceed to act606. In some embodiments, the process 600 may proceed to act 614 if thequality of the uterine contraction signal does not exceed a thresholdquality, and otherwise proceed to act 606. In some embodiments, theprocess 600 may proceed to act 614 if either the quality of the fetalheartbeat signal or the quality of the uterine contraction signal doesnot exceed a threshold quality, and otherwise proceed to act 606. Insome embodiments, the process 600 may proceed to act 614 if a combinedquality of the fetal heartbeat signal and quality of the uterinecontraction signal does not exceed a threshold quality, and otherwiseproceed to act 606. For example, the combined quality may be the mean(e.g., arithmetic or geometric) of the quality of the fetal heartbeatsignal and the quality of the uterine contraction signal. In someembodiments, determining the quality may be performed by the ultrasounddevice. In some embodiments, determining the quality may be performed bya processing device in communication with the ultrasound device.

In some embodiments, acts 608-614 may be absent. For example, theultrasound system may configure the ultrasound device to collectultrasound data from a particular region in act 606 and not determinewhether the ultrasound beam should be subsequently re-steered. Or, insome embodiments, the process 600 may proceed from act 606 to act 602.In other words, after a monitoring period, the ultrasound system mayperform a wide sweep rather than a narrow sweep. In some embodiments,acts 612-614 may be absent. For example, the ultrasound system mayconfigure the ultrasound device to collect ultrasound data from aparticular region scanned in act 608 regardless of whether ultrasounddata collected in act 608 exceeds a threshold quality.

Referring now to FIG. 7, the process 700 is the same as the processes300 and 500, with the following differences. In act 704, the ultrasoundsystem detects fetal heartbeat and/or uterine contraction signals fromthe collected sets of ultrasound. Further description of detecting fetalheartbeat signals may be found with reference to the process 200.Further description of detecting fetal heartbeat signals may be foundwith reference to the process 400. In some embodiments, the ultrasoundsystem may detect both fetal heartbeat and uterine contraction signalsfrom the collected sets of ultrasound data. In some embodiments, theultrasound system may detect either fetal heartbeat or uterinecontraction signals from the collected sets of ultrasound data.

In act 706, the ultrasound system automatically configures theultrasound device to collect further ultrasound data from a regionwithin the subject corresponding to a set of ultrasound data based on aquality of its fetal heartbeat and/or uterine contraction signal.Further description of determining the quality of a fetal heartbeatsignal may be found with reference to the process 200. Furtherdescription of determining the quality of a uterine contraction signalmay be found with reference to the process 400. In some embodiments, theregion may be the region from which the set of ultrasound data havingthe highest quality fetal heartbeat signal was collected. In someembodiments, the region may be the region from which the set ofultrasound data having the highest quality uterine contraction signalwas collected. In some embodiments, the region may be the region fromwhich the set of ultrasound data having the highest combined quality ofits fetal heartbeat and uterine contraction signals was collected. Forexample, the combined quality may be the mean (e.g., arithmetic orgeometric) of the quality of the fetal heartbeat signal and the qualityof the uterine contraction signal. It should be appreciated that theultrasound system may monitor the fetal heartbeat and uterinecontraction signals from the same region within the subject. It shouldalso be appreciated that the ultrasound system may monitor the fetalheartbeat signal at a higher sampling rate, such as 20-30 frames ofultrasound data per second, than the sampling rate at which the uterinecontraction signal is monitored, such as 1 frame of ultrasound data persecond, because the heartrate may be faster than the rate ofcontractions.

In act 708, the ultrasound system determines if a quality of a fetalheartbeat and/or uterine contraction signal in the collected sets ofultrasound data exceed a threshold quality. In some embodiments, theprocess 700 may proceed to act 710 if the quality of the fetal heartbeatsignal does not exceed a threshold quality, and otherwise continue withact 708. In some embodiments, the process 700 may proceed to act 710 ifthe quality of the uterine contraction signal does not exceed athreshold quality, and otherwise continue with act 708. In someembodiments, the process 700 may proceed to act 710 if either thequality of the fetal heartbeat signal or the quality of the uterinecontraction signal does not exceed a threshold quality, and otherwisecontinue with act 708. In some embodiments, the process 700 may proceedto act 710 if a combined quality of the fetal heartbeat signal andquality of the uterine contraction signal does not exceed a thresholdquality, and otherwise continue with act 708. For example, the combinedquality may be the mean (e.g., arithmetic or geometric) of the qualityof the fetal heartbeat signal and the quality of the uterine contractionsignal. In some embodiments, determining the quality may be performed bythe ultrasound device. In some embodiments, determining the quality maybe performed by a processing device in communication with the ultrasounddevice.

In some embodiments, acts 708-710 may be absent. For example, theultrasound system may configure the ultrasound device to collectultrasound data from a particular region in act 506 and not determinewhether the ultrasound beam should be subsequently re-steered. Or, insome embodiments, the process 700 may proceed from act 706 to act 702.In other words, after a monitoring period, the ultrasound system mayperform a wide sweep rather than a narrow sweep.

It should be appreciated that monitoring the fetal heartbeat and uterinecontraction signals may happen at the same time within the same device.In some embodiments, as described above with reference to the processes200-500, monitoring the fetal heartbeat and uterine contraction signalsmay be done by switching back and forth between monitoring the fetalheartbeat signal and monitoring the uterine contraction signal. Forexample, the system may find the heartbeat signal, then find thecontraction signal, then find the heartbeat signal, etc. In someembodiments, uterine contraction monitoring may occur less frequently,as described above. In some embodiments, monitoring the fetal heartbeatand uterine contraction signals may be done by interleaving. Forexample, some of the transmit events (e.g., performed in theconfiguration and detection acts in the processes 600 and 700) may beperformed for monitoring the fetal heartbeat signal, and some transmitevents may be performed for monitoring the uterine contraction signal.Transmit events for monitoring a specific signal may not necessarily begrouped together in time, as the processing routines may separate thedata corresponding to the fetal heartbeat and uterine contractionsignals upon collection. In some embodiments, monitoring the fetalheartbeat and the uterine contraction signals may include using the sameultrasound data. For example, certain transmit events or every transmitevent (e.g., performed in the configuration and detection acts in theprocesses 600 and 700) may be used by the processing to detect either orboth the fetal heartbeat signal and the uterine contraction signal.

In some embodiments, during monitoring of a fetal heartbeat and/oruterine contraction signal (e.g., in acts 106, 206, 306, 406, 506, 606,and 706), the ultrasound device may output the fetal heartbeat and/oruterine contraction signal for display. For example, the ultrasounddevice may transmit the fetal heartbeat and/or uterine contractionsignals over a communication link to a processing device, which may thendisplay the fetal heartbeat signal or the uterine contraction signal asone or more graphs on its display screen. As described above, theprocessing device may be, for example, a mobile phone, tablet, laptop,the processing device of a standard cardiotocography system, or anothertype of electronic device. In some embodiments, the ultrasound patchdevice may transmit the fetal heartbeat and/or uterine contractionsignal over a wired communication link (e.g., over Ethernet, a UniversalSerial Bus (USB) cable or a Lightning cable). In some embodiments, theultrasound patch device may transmit the fetal heartbeat and/or uterinecontraction signal over a wireless communication link (e.g., over aBLUETOOTH, WiFi, ZIGBEE, or cellular (e.g., 3G, LTE, or CAT-M1) wirelesscommunication link). In embodiments in which the processing device is aprocessing device of a standard CTG system, the ultrasound device mayinclude an output port configured to couple to one end of a cable, theother end of which is configured be coupled to the processing device ofthe CTG system. For example, in the case of USB communication, theultrasound device may include a USB port and circuitry capable ofcommunication according to the USB protocol. The processing device ofthe cardiotocography system may then display the fetal heartbeat and/oruterine contraction signal. In other words, the ultrasound devicedescribed herein, rather than the cardiotocography system's owntransducer, may transmit the fetal heartbeat and/or uterine contractionsignal to the processing device of the cardiotocography system fordisplay. In some embodiments, the processing device may process and/orcondition the fetal heartbeat and/or uterine contraction signals priorto display.

In some embodiments, instead of or in addition to the processes 100-700,the ultrasound system may configure the ultrasound device to collect atime series of ultrasound data, where the ultrasound data at each pointin time at which it is collected is from a three-dimensional volume inthe subject. The ultrasound system may detect the fetal heartbeat and/oruterine contraction signals from the three-dimensional volume, using themethods described above (e.g., with reference to the processes 200 and400). The ultrasound data from the three-dimensional volume at eachpoint in time at which it is collected may be collected using a widesweep (e.g., as described in act 102). Assuming that thethree-dimensional volume encompasses the appropriate regions within thesubject where the fetal heartbeat and/or uterine contraction signal canbe detected, it may not be necessary to steer an ultrasound beam to aparticular region to monitor the fetal heartbeat and/or uterinecontraction signal (e.g., as described in act 106) nor may it benecessary to perform a narrow sweep to re-steer the ultrasound beam(e.g., as described in act 108). In some embodiments, undersampling orthree-dimensional plane wave reconstruction with a low number oftransmit plane angles may be used to collect the time series ofthree-dimensional data at a sufficiently high rate to detect the fetalheartbeat.

As described above, any of the statistical models described in thisapplication may be stored and run on the ultrasound device. For example,the ultrasound device may include one or more chips designed foroperating statistical models. The chips may be artificial intelligence(AI) accelerator chips, such as tensor processing units (TPUs)). Any ofthe analyses described herein, such as detecting fetal heartbeat signalsand/or uterine contraction signals, determining fetal heart rate,detecting medically noteworthy signals, and/or determining the qualityof fetal heartbeat and/or uterine contraction signals, may be performedon the ultrasound device (and may or may not include use of statisticalmodels). The ultrasound device may be considered self-contained in thatit may perform all the described analysis on the device, rather thantransmitting data to an external processing device for analysis.

FIG. 8 is a perspective view of an example ultrasound patch 810, inaccordance with certain embodiments described herein. The ultrasoundpatch 810 includes an upper housing 814, a lower housing 816, a circuitboard 818, and a dressing 828. For purposes of illustration, the upperhousing 814 of the ultrasound patch 810 is depicted in a transparentmanner to depict exemplary locations of various internal components ofthe ultrasound patch 810. The circuit board 818 supports a heat sink 820and communications circuitry 824.

In some embodiments, the communication circuitry 824 includes one ormore short- or long-range communication platforms. Exemplary short-rangecommunication platforms include Bluetooth (BT), Bluetooth Low Energy(BLE), and Near-Field Communication (NFC). Exemplary long-rangecommunication platforms include WiFi and Cellular (e.g., 3G, LTE, orCAT-M1). While not shown, the communication circuitry 824 may includefront-end radio, antenna and other processing circuitry configured tocommunicate radio signals to an external processing electronic device(not shown). In some embodiments, the ultrasound patch 810 may beconfigured, using the communication circuitry 824, to wirelessly offloadsignals (e.g., fetal heartbeat and/or uterine contraction signals)collected by the ultrasound patch 810 to a processing device (not shown)for further processing, display, and/or storage. In some embodiments,the ultrasound patch 810 may offload the signals to the processingdevice in real-time. The ultrasound patch 810 may receive, with thecommunication circuitry 824, control parameters communicated from theprocessing device to the ultrasound patch 810. The control parametersmay dictate the scope of the ultrasound data/image to be obtained byultrasound patch 810. The circuit board 818 may further includeprocessing circuitry (not shown), including one or more controllersand/or field-programmable gate arrays (FPGAs) to direct communicationthrough the communication circuitry 824. The dressing 828 may provide anadhesive surface for adhering the ultrasound patch 810 (in particular,the lower housing 816) to the skin of a patient. One non-limitingexample of such a dressing 828 is Tegaderm™, a transparent medicaldressing available from 3M Corporation.

FIG. 9 is an exploded view of the ultrasound patch 810 in accordancewith certain embodiments described herein. FIG. 9 illustrates aplurality of through vias 926 (e.g., copper) that may be used for athermal connection between the heat sink 820 and one or more CMOS chips(not shown in FIG. 9, but shown as 1034 in FIG. 10). The lower housing816 includes an opening 930 that aligns with another opening 932 in thedressing 828. FIG. 9 further illustrates that the circuit board 818supports a battery 922.

FIG. 10 is another exploded view of the ultrasound patch 810, inaccordance with certain embodiments described herein. FIG. 10illustrates the location of an integrated CMOS chip 1034 on the circuitboard 818. For example, the CMOS chip 1034 may be a chip includingultrasound transducers and an application-specific integrated circuit(ASIC). The CMOS chip 1034 may be an ultrasound-on-chip (i.e., a deviceincluding micromachined ultrasound transducers integrated with an ASICor other semiconductor die containing integrated circuitry). In someembodiments, the CMOS chip 1034 may instead be multiple chips packagedtogether (e.g., in a stacked configuration). Further description of theCMOS chip 1034 in certain embodiments may be found in U.S. patentapplication Ser. No. 15/626,711 titled “UNIVERSAL ULTRASOUND DEVICE ANDRELATED APPARATUS AND METHODS,” filed on Jun. 19, 2017 and published asU.S. Pat. App. Publication No. 2017-0360399 A1 and/or U.S. patentapplication Ser. No. 16/192,603 titled “ULTRASOUND APPARATUSES ANDMETHODS FOR FABRICATING ULTRASOUND DEVICES,” filed on Nov. 15, 2018 andpublished as U.S. Pat. App. Publication No. 2019-0142387 A1. FIG. 10further illustrates an acoustic lens 1036 mounted over the CMOS chip1034. The acoustic lens 1036 may be configured to protrude throughopenings 930 and 932 to make contact with the skin of a patient.

FIG. 11 is an illustration of the ultrasound patch 810 coupled to apatient 1112, in accordance with certain embodiments described herein.FIG. 11 illustrates the ultrasound patch 810 coupled to a regionadjacent to the uterus of the patient 1112, such that the ultrasoundpatch 810 may detect fetal heartbeat and/or uterine contraction signals.

FIG. 12 is a perspective view of an example ultrasound patch 1210, inaccordance with certain embodiments described herein. The ultrasoundpatch 1210 includes an upper housing 1214, a lower housing 1216, acircuit board 1218, a dressing 1228, a heat sink 1220, andcommunications circuitry 1224. The upper housing 1214 and the lowerhousing 1216 differ from the upper housing 814 and the lower housing 816in that the upper housing 1214 and the lower housing 1216 include a port1238 disposed in an opening in the upper housing 1214 and lower housing1216 (or, in some embodiments, just one of the housings). The port 1238may be configured to accept one end of a cable. For example, in the caseof USB communication, the port 1238 may be a USB port configured toaccept one end of a USB cable. The other end of the cable may beconfigured to couple to a processing device. The processing device maybe, for example, a mobile phone, tablet, laptop, the processing deviceof a standard cardiotocography system, or another type of electronicdevice. The communications circuitry 1224 may be configured to transmitand receive data through the port 1238. For example, the communicationscircuitry 1224 may be configured to transmit and receive data accordingto a certain protocol, such as the Universal Serial Bus (USB) protocol.The circuit board 1218 supports the communications circuitry 1224 andthe heat sink 1220. Further description of the dressing 1228 may befound with reference to the dressing 828. Additionally, the circuitboard 1218 may support a CMOS chip (e.g., the CMOS chip 1034) which isnot be visible in FIG. 12.

FIG. 13 illustrates an example alternative fastening mechanism for anultrasound patch 1310 in accordance with certain embodiments describedherein. The ultrasound patch 1310 may be the ultrasound patch 810 or theultrasound patch 1210, for example. The ultrasound patch 1310 includes atop housing 1314, which may be the top housing 814 or the top housing1214. The fastening mechanism includes a buckle 1340, a post 1342, andslots 1344. The top housing 1314 is affixed to the buckle 1340 via thepost 1342 using, for example, a threaded engagement between the buckle1340 and the post 1342. Other attachment configurations are alsocontemplated, however. The buckle 1342 includes slots 1344 foraccommodating a strap.

FIG. 14 is an illustration of the ultrasound patch 1310 fastened to apatient 1412, in accordance with certain embodiments described herein.FIG. 14 illustrates a strap 1446 threaded through the slots 1344,wrapped around the patient 1412, and appropriately tightened in order tosecure the ultrasound patch 1310 to the desired region of the patient1412. In FIG. 14, the ultrasound patch 1310 is secured to a regionadjacent to the uterus of the patient 1412, such that the ultrasoundpatch 1310 may detect fetal heartbeat and/or uterine contractionsignals.

FIG. 15 is a schematic block diagram of an example ultrasound system1500, in accordance with certain embodiments described herein. As shown,the ultrasound system 1500 includes an ultrasound device 1502, aprocessing device 1504, and a communication link 1506. The ultrasounddevice 1502 may be any of the ultrasound devices (e.g., a wearableultrasound device, such as a patch) described herein. The processingdevice 1504 may be any of the processing devices described herein. Theultrasound device 1502 includes ultrasound circuitry 1508, processingcircuitry 1510, memory circuitry 1512, and communication circuitry 1514.The processing device 1504 includes processing circuitry 1516, memorycircuitry 1518, communication circuitry 1520, and a display screen 1522.The ultrasound device 1502 is configured to communicate with theprocessing device 1504 over the communication link 1506. Thecommunication link 1506 may include a wired connection and/or a wirelessconnection. The ultrasound device 1502 may be any of the ultrasounddevices described herein. The processing device 1504 may be any of theprocessing devices described herein.

The ultrasound device 1502 may be configured to generate ultrasound datathat may be employed to generate an ultrasound image. The ultrasounddevice 1502 may be constructed in any of a variety of ways. In someembodiments, the ultrasound device 1502 includes a transmitter thattransmits a signal to a transmit beamformer which in turn drivestransducer elements within a transducer array to emit pulsed ultrasonicsignals into a structure, such as a patient. The pulsed ultrasonicsignals may be back-scattered from structures in the body, such as bloodcells or muscular tissue, to produce echoes that return to thetransducer elements. These echoes may then be converted into electricalsignals by the transducer elements and the electrical signals arereceived by a receiver. The electrical signals representing the receivedechoes are sent to a receive beamformer that outputs ultrasound data.The ultrasound circuitry 1508 may be configured to generate theultrasound data. The ultrasound circuitry 1508 may include anultrasound-on-chip, and thus may include one or more ultrasonictransducers monolithically integrated onto a single semiconductor die.The ultrasonic transducers may include, for example, one or morecapacitive micromachined ultrasonic transducers (CMUTs), one or moreCMOS (complementary metal-oxide-semiconductor) ultrasonic transducers(CUTs), one or more piezoelectric micromachined ultrasonic transducers(PMUTs), and/or one or more other suitable ultrasonic transducer cells.In some embodiments, the ultrasonic transducers may be formed on thesame chip as other electronic components in the ultrasound circuitry1508 (e.g., transmit circuitry, receive circuitry, control circuitry,power management circuitry, and processing circuitry) to form amonolithic ultrasound device. In some embodiments, the ultrasoundtransducers may be arranged in an array, such as a two-dimensionalarray. The two-dimensional array of ultrasound transducers may enablethe ultrasound circuitry 1508 to steer ultrasound beams in differentdirections (e.g., to steer the ultrasound beams at different azimuthaland elevational angles) and thereby collect three-dimensional ultrasounddata of a volume within a subject.

The processing circuitry 1510 may control operation of the ultrasounddevice 1502, and in particular, operation of the ultrasound circuitry1508, the memory circuitry 1512, and the communication circuitry 1514.As one example, the processing circuitry 1510 may be configured tocontrol collection of ultrasound data by the ultrasound device 1502. Asanother example, the processing circuitry 1510 may be configured tostore and operate any of the statistical models described herein. Theportion of the processing circuitry 1510 configured to store and operatestatistical models may be implemented as artificial intelligence (AI)accelerator chips, which may include one or more tensor processing units(TPUs). TPUs may be application-specific integrated circuits (ASICs)specifically designed for operating statistical models, machinelearning, and/or deep learning. The TPUs may be employed to, forexample, accelerate the inference phase of a neural network. The memorycircuitry 1512 may include non-transitory computer-readable storagemedia. The processing circuitry 1510 may control writing data to andreading data from the memory circuitry 1512 in any suitable manner. Toperform any of the functionality of the ultrasound device 1502 describedherein, the processing circuitry 1510 may execute one or moreprocessor-executable instructions stored in one or more non-transitorycomputer-readable storage media (e.g., the memory circuitry 1512), whichmay serve as non-transitory computer-readable storage media storingprocessor-executable instructions for execution by the processingcircuitry 1510. The communication circuitry 1514 may be configured toenable communication between the ultrasound device 1502 and theprocessing device 1504 over the communication link 1506. Thecommunication circuitry 1514 may include an antenna and circuitrycapable of transmitting and receiving signals according to a certainwireless communication protocol (e.g., WiFi, BLUETOOTH, Zigbee, orcellular (e.g., 3G, LTE, or CAT-M1) and/or a data connector port foraccepting a data connector of a particular type and circuitry capable oftransmitting and receiving signals according to a certain protocol. Insome embodiments, the communication circuitry 1514 may include circuitryfor communication according to multiple protocols and/or circuitry forwired and wireless communication. The ultrasound device 1502 may beconfigured as a wearable ultrasound device, such as a patch. Wearableultrasound devices are described further with reference to FIGS. 8-14.

The processing device 1504 may be configured to process ultrasound datafrom the ultrasound device 1502 to generate ultrasound images. Theprocessing may be performed by, for example, the processing circuitry1516. The processing circuitry 1516 may also be adapted to control theacquisition of ultrasound data with the ultrasound device 1502. Theultrasound data may be processed in real-time during a scanning sessionas the echo signals are received. In some embodiments, the displayedultrasound image may be updated at a rate of at least 5 Hz, at least 10Hz, at least 20 Hz, at a rate between 5 and 60 Hz, at a rate of morethan 20 Hz, etc. For example, ultrasound data may be acquired even asimages are being generated based on previously acquired data and while alive ultrasound image is being displayed. As additional ultrasound datais acquired, additional frames or images generated from more-recentlyacquired ultrasound data are sequentially displayed. Additionally, oralternatively, the ultrasound data may be stored temporarily in a bufferduring a scanning session and processed in less than real-time.

The processing circuitry 1516 of the processing device 1504 may also beconfigured to control operation of the processing device 1504. Theprocessing circuitry 1516 may be configured to control operation of thememory circuitry 1518, the communication circuitry 1520, and the displayscreen 1522. The memory circuitry 1518 may include non-transitorycomputer-readable storage media. The processing circuitry 1516 maycontrol writing data to and reading data from the memory circuitry 1518in any suitable manner. To perform any of the functionality of theprocessing device 1504 described herein, the processing circuitry 1516may execute one or more processor-executable instructions stored in oneor more non-transitory computer-readable storage media (e.g., the memorycircuitry 1518), which may serve as non-transitory computer-readablestorage media storing processor-executable instructions for execution bythe processing circuitry 1516.

The communication circuitry 1520 may be configured to enablecommunication between the processing device 1504 and the ultrasounddevice 1502 over the communication link 1506. When the communicationcircuitry 1520 is configured for wired communication, the communicationcircuitry 1520 may include a data connector port for accepting a dataconnector of a particular type and circuitry capable of transmitting andreceiving signals according to a certain protocol. For example, in thecase of USB communication, the communication circuitry 1520 may includea USB port and circuitry capable of communication according to the USBprotocol. When the communication circuitry 1520 is configured forwireless communication, the communication circuitry 1520 may include anantenna and circuitry capable of transmitting and receiving signalsaccording to a certain protocol. In some embodiments, the communicationcircuitry 1520 may include circuitry for communication according tomultiple protocols and/or circuitry for wired and wirelesscommunication. The display screen 1522 may be configured to displayimages and/or videos, and may be, for example, a liquid crystal display(LCD), a plasma display, and/or an organic light emitting diode (OLED)display on the processing device 1504.

It should be appreciated that the processing device 1504 may beimplemented in any of a variety of ways. For example, the processingdevice 1504 may be implemented as a handheld device such as a mobilesmartphone or a tablet, as a portable device that is not a handhelddevice such as a laptop, or as a stationary device such as a desktopcomputer or the processing device of a standard cardiotocography system.

For further description of ultrasound devices and systems, as well asdescription of ultrasound-on-chips, see U.S. patent application Ser. No.15/415,434 titled “UNIVERSAL ULTRASOUND DEVICE AND RELATED APPARATUS ANDMETHODS,” filed on Jan. 25, 2017 and published as U.S. Pat. App.Publication No. 2017-0360397 A1 (and assigned to the assignee of theinstant application) and/or U.S. patent application Ser. No. 16/192,603titled “ULTRASOUND APPARATUSES AND METHODS FOR FABRICATING ULTRASOUNDDEVICES,” filed on Nov. 15, 2018 and published as U.S. Pat. App.Publication No. 2019-0142387 A1, which are incorporated by referenceherein in their entireties.

FIG. 15 should be understood to be non-limiting. For example, theultrasound system 1500, the ultrasound device 1502, and the processingdevice 1504 may include fewer or more components than shown.

Various aspects of the present disclosure may be used alone, incombination, or in a variety of arrangements not specifically describedin the embodiments described in the foregoing and is therefore notlimited in its application to the details and arrangement of componentsset forth in the foregoing description or illustrated in the drawings.For example, aspects described in one embodiment may be combined in anymanner with aspects described in other embodiments.

Various inventive concepts may be embodied as one or more processes, ofwhich examples have been provided. The acts performed as part of eachprocess may be ordered in any suitable way. Thus, embodiments may beconstructed in which acts are performed in an order different thanillustrated, which may include performing some acts simultaneously, eventhough shown as sequential acts in illustrative embodiments. Further,one or more of the processes may be combined and/or omitted, and one ormore of the processes may include additional steps.

The indefinite articles “a” and “an,” as used herein in thespecification and in the claims, unless clearly indicated to thecontrary, should be understood to mean “at least one.”

The phrase “and/or,” as used herein in the specification and in theclaims, should be understood to mean “either or both” of the elements soconjoined, i.e., elements that are conjunctively present in some casesand disjunctively present in other cases. Multiple elements listed with“and/or” should be construed in the same fashion, i.e., “one or more” ofthe elements so conjoined. Other elements may optionally be presentother than the elements specifically identified by the “and/or” clause,whether related or unrelated to those elements specifically identified.

As used herein in the specification and in the claims, the phrase “atleast one,” in reference to a list of one or more elements, should beunderstood to mean at least one element selected from any one or more ofthe elements in the list of elements, but not necessarily including atleast one of each and every element specifically listed within the listof elements and not excluding any combinations of elements in the listof elements. This definition also allows that elements may optionally bepresent other than the elements specifically identified within the listof elements to which the phrase “at least one” refers, whether relatedor unrelated to those elements specifically identified.

Use of ordinal terms such as “first,” “second,” “third,” etc., in theclaims to modify a claim element does not by itself connote anypriority, precedence, or order of one claim element over another or thetemporal order in which acts of a method are performed, but are usedmerely as labels to distinguish one claim element having a certain namefrom another element having a same name (but for use of the ordinalterm) to distinguish the claim elements.

As used herein, reference to a numerical value being between twoendpoints should be understood to encompass the situation in which thenumerical value can assume either of the endpoints. For example, statingthat a characteristic has a value between A and B, or betweenapproximately A and B, should be understood to mean that the indicatedrange is inclusive of the endpoints A and B unless otherwise noted.

The terms “approximately” and “about” may be used to mean within ±20% ofa target value in some embodiments, within ±10% of a target value insome embodiments, within ±5% of a target value in some embodiments, andyet within ±2% of a target value in some embodiments. The terms“approximately” and “about” may include the target value.

Also, the phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having,” “containing,” “involving,” andvariations thereof herein, is meant to encompass the items listedthereafter and equivalents thereof as well as additional items.

Having described above several aspects of at least one embodiment, it isto be appreciated various alterations, modifications, and improvementswill readily occur to those skilled in the art. Such alterations,modifications, and improvements are intended to be object of thisdisclosure. Accordingly, the foregoing description and drawings are byway of example only.

What is claimed is:
 1. An apparatus, comprising: an ultrasound systemconfigured to: configure an ultrasound device to collect multiple setsof ultrasound data from multiple regions within a subject; detect fetalheartbeat and/or uterine contraction signals from the collected sets ofultrasound data; and monitor the fetal heartbeat and/or uterinecontraction signals by automatically configuring the ultrasound deviceto collect further ultrasound data from a region within the subjectcorresponding to one of the multiple sets of ultrasound data based on aquality of its fetal heartbeat and/or uterine contraction signal.
 2. Theapparatus of claim 1, wherein the ultrasound device comprises a wearableultrasound device.
 3. The apparatus of claim 2, wherein the wearableultrasound device comprises an ultrasound patch coupled to a subject. 4.The apparatus of claim 2, wherein the wearable ultrasound devicecomprises a two-dimensional array of ultrasonic transducers.
 5. Theapparatus of claim 1, wherein each of the multiple sets of ultrasounddata comprises a time series of an A-line.
 6. The apparatus of claim 1,wherein each of the multiple sets of data comprises a time series ofultrasound images collected from a two-dimensional slice within thesubject.
 7. The apparatus of claim 1, wherein the ultrasound system isconfigured, when detecting the fetal heartbeat signals from thecollected sets of ultrasound data, to use an M-mode ultrasoundtechnique.
 8. The apparatus of claim 1, wherein the ultrasound system isconfigured, when automatically configuring the ultrasound device tocollect the further ultrasound data from the region within the subjectcorresponding to one of the multiple sets of ultrasound data based onthe quality of its fetal heartbeat and/or uterine contraction signal, toconfigure the ultrasound device to use a two-dimensional array ofultrasonic transducers to steer an ultrasound beam in three dimensionsto the region in order to collect the further ultrasound data.
 9. Theapparatus of claim 1, wherein the ultrasound system is configured, whenautomatically configuring the ultrasound device to collect the furtherultrasound data from the region within the subject corresponding to oneof the multiple sets of ultrasound data based on the quality of itsfetal heartbeat and/or uterine contraction signal, to configure theultrasound device to collect the further ultrasound data withoutcollecting ultrasound data from other of the multiple regions within thesubject.
 10. The apparatus of claim 1, wherein the ultrasound system isconfigured, when automatically configuring the ultrasound device tocollect the further ultrasound data from the region within the subjectcorresponding to one of the multiple sets of ultrasound data based onthe quality of its fetal heartbeat and/or uterine contraction signal, toconfigure the ultrasound device to collect the further ultrasound datafrom a region within the subject corresponding to a set of ultrasounddata that has a highest quality fetal heartbeat signal, a highestquality uterine contraction signal, or a highest combined quality offetal heartbeat and uterine contraction signals.
 11. The apparatus ofclaim 1, wherein the ultrasound system is further configured to:continuously or periodically monitor a quality of the fetal heartbeatand/or uterine contraction signals; and configure the ultrasound deviceto collect multiple sets of ultrasound data from a subset of themultiple regions within the subject based on the quality of the fetalheartbeat and/or uterine contraction signals not exceeding a thresholdquality.
 12. The apparatus of claim 11, wherein the subset of theregions is a first particular percentage of regions approximatelycentered around the region within the subject from which the furtherultrasound data was collected.
 13. The apparatus of claim 11, whereinthe subset of the regions is along a spiral curve around the regionwithin the subject from which the further ultrasound data was collected.14. The apparatus of claim 1, wherein the ultrasound system isconfigured to steer an ultrasound beam to one region to monitor thefetal heartbeat signal and to steer the ultrasound beam to anotherregion to monitor the uterine contraction signal.
 15. The apparatus ofclaim 1, wherein the ultrasound system is configured to monitor thefetal heartbeat signal at a higher sampling rate than a sampling rate atwhich the uterine contraction signal is monitored.
 16. The apparatus ofclaim 1, wherein the ultrasound system is further configured to transmitthe fetal heartbeat and/or uterine contraction signals over acommunication link to a processing device configured to display thefetal heartbeat signal and/or uterine contraction signals as one or moregraphs on its display screen.
 17. The apparatus of claim 16, wherein theprocessing device comprises a mobile phone, tablet, laptop, or aprocessing device of a standard cardiotocography system.
 18. Anapparatus, comprising: an ultrasound system configured to: sweep avolume to collect ultrasound data; detect a fetal heartbeat and/oruterine contraction signal in the ultrasound data; and automaticallysteer an ultrasound beam to monitor the fetal heartbeat and/or uterinecontraction signal.
 19. The apparatus of claim 18, where the ultrasounddata comprises multiple sets of ultrasound data collected at differentlocations within the volume.
 20. The apparatus of claim 18, wherein theultrasound system is further configured to determine a location wherethe fetal heartbeat and/or uterine contraction signal is detectable ordetectable at a highest quality.
 21. The apparatus of claim 18, whereinthe ultrasound system is further configured to sweep a modified volumeto collect ultrasound data.
 22. The apparatus of claim 21, wherein: theultrasound system is further configured to determine a location wherethe fetal heartbeat and/or uterine contraction signal is detectable ordetectable at the highest quality; and the ultrasound system isconfigured, when sweeping the modified volume to collect ultrasounddata, to sweep a volume modified based on the location where the fetalheartbeat and/or uterine contraction signal was previously monitored.23. The apparatus of claim 21, wherein the modified volume is collectedwith a sweep that is centered around the location where the fetalheartbeat and/or uterine contraction signal was previously monitored.